Inventories, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Lime and limestone inventories:
Raw materials	$ 2,905	$ 4,279
Finished goods	2,787	2,866
Total	5,692	7,145
Service parts inventories	9,068	8,065
Total inventories	$ 14,760	$ 15,210

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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